U.S. Pat. Nos. 7,213,975 and 7,393,144 illustrate a schematic cross-section of a hybrid fiber/copper communications cable. The hybrid cable, illustrated in FIG. 4 of U.S. Pat. No. 7,213,975 and U.S. Pat. No. 7,393,144, includes a pair of jacketed optical fibers and four jacketed copper wires, extending adjacent a linearly extending strength member. This is one example configuration of a hybrid cable that is used in the telecommunications industry. Other configurations of hybrid cables are also known, with more or fewer optical fibers and/or copper wires.
For example, according to another example configuration, a hybrid cable 5 might have six copper conductors 10, two fibers 12, and one strength member 14, all surrounded by a metal braid 16 for grounding. The metal braid 16 is surrounded by an outer cable jacket 18. A cable filler 20 made out of pvc material may also be used to surround the inner components.
Two of the copper wires 10 might be used for communications purposes, four of the copper wires 10 might be used for transmitting power, and the two optical fibers 12 are used for transmitting optical signals. When used in, for example, a broadcast camera environment, one of the optical fibers 12 may be used to transmit video and related audio signals to the camera and the second optical fiber 12 may be used to transmit video and audio captured by the camera to the production facility or some other location. One or more pairs of copper conductors 10 may be used to provide power to operate the camera, while the other pair of copper conductors 10 may be used to provide communications between the production facility and the camera operator. The number of fiber strands and copper conductors extending within the hybrid cable 5 may be varied as required to support the desired usage and communication bandwidth of the camera.
In using these hybrid cables with optical fibers, it is important to prepare the cable 5 by cutting each of the different elements (copper wires 10, optical fibers 12, strength member 14, grounding braid 16, cable jacket 18, etc.) to the correct lengths. The fibers 12 in these cables are normally sensitive to sharp bends. A sharp bend on a fiber inside a connector can easily cause a high insertion loss and cause the optical link system to fail. Some optical systems have a loss budget or allowable attenuation limit of about 10 dB maximum. A sharp bend in the optic fiber 12 can easily pass this threshold and lead to loss of signal. It is also important to ensure that the components within the cable are not cut too short in length, preventing their proper termination within the connector.
Conventionally, it has been common to measure each of the components of the cable 5 to a desired length by using a ruler, mark the desired cut point, and cut each component separately by hand at the cut point. This method has been known to lead to inconsistent results and be time consuming. There is not much room for variations within some connectors, wherein the components must be cut precisely to achieve proper termination. Improvements in cable preparation for hybrid cables and other types of cables utilizing a number of different components are desired.